1. Field of the Invention
The present invention relates to a driving apparatus for moving an object and an exposure apparatus including the same.
2. Description of the Related Art
Conventionally, as typical exposure apparatuses used to manufacture semiconductor devices or the like, there are step-and-repeat exposure apparatuses (also referred to as steppers) which sequentially transfer the pattern of a master (reticle or mask) onto a plurality of exposure regions on a substrate (wafer or glass substrate) by exposure while moving the substrate stepwise, or step-and-scan exposure apparatuses (also referred to as scanners) which repeat step movement and scanning exposure to repeatedly transfer a pattern onto a plurality of regions on a substrate by exposure. Especially, the step-and-scan exposure apparatuses are expected to be a mainstream in the future because they limit light through a slit and use only a portion relatively close to the optical axis of the projection optical system, and therefore, allow exposure using a precise and wide-angled fine pattern.
Such an exposure apparatus has a stage unit (wafer stage or reticle stage) for moving a wafer or a reticle at a high speed and positioning it. When the stage is driven, the inertial force generates a reaction force in accordance with acceleration/deceleration. This reaction force is transmitted to a platen to swing or vibrate it. This may excite natural vibration of the mechanical system of the exposure apparatus and generate high-frequency vibration to impede high-speed and accurate positioning.
Several proposals have been made to solve the problem of the reaction force. For example, an apparatus disclosed in Japanese Patent Laid-Open No. 5-77126 employs a system for preventing swing of the stage platen due to a reaction force by supporting the stator of a linear motor for driving the stage on the floor independently of the stage platen. An apparatus disclosed in Japanese Patent Laid-Open No. 5-121294 uses a system for decreasing swing of the apparatus due to a reaction force by applying, to a machine frame supporting a wafer stage and a projecting lens, a compensation force equivalent to the reaction force according to drive of the stage by a force actuator which generates a force in the horizontal direction.
In both the prior arts, however, although swing of the stage unit itself can be reduced, the reaction force according to drive of the stage is transmitted to the floor directly or through a member which is substantially integrated with the floor. Since the floor vibrates, apparatuses set around the exposure apparatus also vibrate and are adversely affected. Normally, a floor on which an exposure apparatus is set has a natural frequency of about 20 to 40 Hz. When natural vibration of the floor is excited according to the operation of the exposure apparatus, the peripheral apparatuses are considerably adversely affected.
Recently, the stage acceleration is constantly increasing along with improvement of the process speed (throughput). For example, in a step-and-scan exposure apparatus, the maximum acceleration of the reticle stage is 4 G, and that of the wafer stage is 1 G. In addition, the stage mass also increases as the reticle or substrate size increases. For this reason, the driving force defined by  less than mass of moving body greater than xc3x97 less than acceleration greater than  is very large, and the reaction force thereof is enormous. Hence, the problem of vibration of the setting floor due to an increase in acceleration and weight is unnegligible.
In addition to the problem of vibration, the apparatuses which are becoming bulky also pose the problem of an increase in occupation area in a manufacturing factory where many manufacturing apparatuses are set.
The present invention has been made in consideration of the above situation, and has as its object to realize highly accurate stage positioning control by decreasing the influence of vibration or swing according to movement of a stage.
It is another object of the present invention to minimize the influence of a reaction force generated upon acceleration/deceleration of a stage on a floor and prevent vibration from being transmitted to another apparatus set on the same floor.
It is still another object of the present invention to reduce the setting area of a driving apparatus and an exposure apparatus.
A driving apparatus according to the first aspect of the present invention comprises a stage which moves with the object mounted thereon, a base member supporting the stage, a reaction force reception structure for receiving a reaction force generated upon driving the stage, and a damp member for damping transmission of vibration with a predetermined frequency range from the reaction force reception structure to a floor.
In the driving apparatus according to the first aspect of the present invention, preferably, the damp member has an elastic support between the floor or a member substantially equivalent to the floor and the reaction force reception structure, and the reaction force reception structure is supported by the floor or the member substantially equivalent to the floor through the elastic support.
In the driving apparatus according to the first aspect of the present invention, the elastic support preferably elastically supports the reaction force reception structure from a lower side and/or from one side.
The driving apparatus according to the first aspect of the present invention preferably further comprises an application section for applying a force between the base member and the reaction force reception structure.
In the driving apparatus according to the first aspect of the present invention, the application section preferably has an actuator for generating a force in a horizontal direction and/or in a vertical direction.
In the driving apparatus according to the first aspect of the present invention, preferably, the stage moves in a horizontal plane, and the application section comprises an actuator for generating a force in an X direction in the horizontal plane and an actuator for generating a force in a Y direction in the horizontal plane.
In the driving apparatus according to the first aspect of the present invention, the application section preferably comprises a linear motor.
In the driving apparatus according to the first aspect of the present invention, a level of a barycenter of the stage preferably substantially equals a level at which the application section applies the force to the reaction force reception structure.
Preferably, the driving apparatus according to the first aspect of the present invention further comprises a mount between the floor or a member substantially equivalent to the floor and the base member, and the base member is supported by the floor or the member substantially equivalent to the floor through the mount.
In the driving apparatus according to the first aspect of the present invention, the mount preferably comprises an air spring.
In the driving apparatus according to the first aspect of the present invention, the reaction force reception structure is preferably arranged under the base member.
In the driving apparatus according to the first aspect of the present invention, the damp member preferably damps transmission of vibration having a frequency containing a natural frequency of the floor from the reaction force reception structure to the floor.
In the driving apparatus according to the first aspect of the present invention, the damp member preferably damps vibration having a frequency not less than 10 Hz from the reaction force reception structure to the floor.
In the driving apparatus according to the first aspect of the present invention, preferably, the stage moves in a horizontal plane, the damp member has an elastic support between a member fixed to the floor and the reaction force reception structure, and the reaction force reception structure is supported from one side by the member fixed to the floor through the elastic support.
In the driving apparatus according to the first aspect of the present invention, preferably, the stage moves in a horizontal plane, the damp member has an elastic support between the floor or a member substantially equivalent to the floor and the reaction force reception structure, and the reaction force reception structure is supported from a lower side by the floor or the member substantially equivalent to the floor through the elastic support.
The driving apparatus according to the first aspect of the present invention preferably further comprises a stage platen having a reference surface in moving the stage, an interferometer for measuring a vertical position of the stage, and a reference mirror paired with the interferometer, the stage platen being supported by the base member, and the reference mirror being fixed to the stage platen.
The driving apparatus according to the first aspect of the present invention preferably further comprises an air outlet port for supplying a temperature-controlled gas to the stage, the air outlet port being supported by the reaction force reception structure.
The driving apparatus according to the first aspect of the present invention is suitable when the air outlet port has a gas filter.
A driving apparatus according to the second aspect of the present invention comprises a stage which moves with the object mounted thereon, a base member supporting the stage, a reaction force reception structure for receiving a reaction force generated upon driving the stage, a first mechanical filter for damping transmission of vibration between the reaction force reception structure and a floor, and a second mechanical filter for damping transmission of vibration between the base member and the floor.
In the driving apparatus according to the second aspect of the present invention, the first mechanical filter preferably damps transmission of vibration with a frequency not less than 10 Hz.
In the driving apparatus according to the second aspect of the present invention, preferably, a lower limit of the frequency of vibration damped by the first mechanical filter is higher than a lower limit of the frequency of vibration damped by the second mechanical filter.
A driving apparatus according to the third aspect of the present invention comprises a stage which moves with the object mounted thereon, a base member supporting the stage, a reaction force reception structure for receiving a reaction force generated upon driving the stage, and an elastic support interposed between the reaction force reception structure and a floor or a member substantially equivalent to the floor, wherein the reaction force reception structure is supported by the floor or the member substantially equivalent to the floor through the elastic support.
A driving apparatus according to the fourth aspect of the present invention is a driving apparatus for moving an object and comprises a stage which moves with the object mounted thereon, a base member supporting the stage, a reaction force reception structure for receiving a reaction force generated upon driving the stage, and an application section for applying a force between the base member and the reaction force reception structure.
In the driving apparatus according to the fourth aspect of the present invention, preferably, the stage moves in a horizontal plane, and the application section has a plurality of actuators for applying a force in a vertical direction between the base member and the reaction force reception structure.
In the driving apparatus according to the fourth aspect of the present invention, preferably, the stage moves in a horizontal plane, and the application section has an actuator for applying a force in a horizontal direction between the base member and the reaction force reception structure.
In the driving apparatus according to the fourth aspect of the present invention, a level of a barycenter of the stage preferably substantially equals a level at which the actuator applies the force to the reaction force reception structure.
A driving apparatus according to the fifth aspect of the present invention comprises a stage which moves with the object mounted thereon, a base member supporting the stage, a reaction force reception structure for receiving a reaction force generated upon driving the stage, an elastic support interposed between the reaction force reception structure and a floor or a member substantially equivalent to the floor, and a mount interposed between the base member and the floor or the member substantially equivalent to the floor, wherein the elastic support and the mount independently support the reaction force reception structure and the base member, respectively.
A driving apparatus according to the sixth aspect of the present invention comprises a stage which moves with the object mounted thereon, a base member supporting the stage, and a reaction force reception structure for receiving a reaction force generated upon driving the stage.
In the driving apparatus according to the sixth aspect of the present invention, the reaction force reception structure is preferably arranged under the base member.
Preferably, the driving apparatus according to the sixth aspect of the present invention further comprises a mount between the base member and the floor or a member substantially equivalent to the floor, and the base member is elastically supported by the floor or the member substantially equivalent to the floor through the mount.
In the driving apparatus according to the sixth aspect of the present invention, the mount preferably comprises an air spring.
The driving apparatus according to the sixth aspect of the present invention preferably further comprises an air outlet port for supplying a temperature-controlled gas to the stage, the air outlet port being supported by the reaction force reception structure.
In the driving apparatus according to the sixth aspect of the present invention, the air outlet port preferably has a gas filter.
An exposure apparatus according to the seventh aspect of the present invention comprises a projection optical system, a master stage, and a substrate stage to which any one of the above driving apparatuses is applied, wherein a pattern of a master mounted on the master stage is transferred to a substrate mounted on the substrate stage.
An exposure apparatus according to the eighth aspect of the present invention comprises a projection optical system, a master stage to which any one of the above driving apparatuses is applied, and a substrate stage, wherein a pattern of a master mounted on the master stage is transferred to a substrate mounted on the substrate stage.
An exposure apparatus according to the ninth aspect of the present invention comprises a projection optical system, and master and substrate stages to which any one of the above driving apparatuses is applied, wherein a pattern of a master mounted on the master stage is transferred to a substrate mounted on the substrate stage.
An exposure apparatus according to the 10th aspect of the present invention comprises a substrate stage which moves with a substrate mounted thereon, a base member supporting the substrate stage, a plurality of first mounts interposed between the base member and a floor or a member substantially equivalent to the floor to elastically support the base member from a lower side, a master stage which moves with a master mounted thereon, a projection optical system, a lens-barrel platen supporting the master stage and the projection optical system, and a plurality of second mounts interposed between the lens-barrel platen and the floor or the member substantially equivalent to the floor to elastically support the lens-barrel platen from the lower side, wherein when viewed from an upper side, the plurality of first mounts are arranged in an inner region of the plurality of second mounts.
In the exposure apparatus according to the 10th aspect of the present invention, preferably, the substrate stage is supported on the base member by three support legs, and the three support legs are arranged in an inner region of the plurality of first mounts when viewed from the upper side.
In the exposure apparatus according to the 10th aspect of the present invention, preferably, the number of first mounts is three or four, and the number of second mounts is three or four.
In the exposure apparatus according to the 10th aspect of the present invention, preferably, the number of first mounts is three, and the three first mounts are arranged so as to substantially make an isosceles triangle as a triangle having representative points of the first mounts as vertices.
An exposure apparatus according to the 11th aspect of the present invention comprises a substrate stage which moves with a substrate mounted thereon, a base member supporting the substrate stage, a plurality of first mounts interposed between the base member and a floor or a member substantially equivalent to the floor to elastically support the base member from a lower side, a master stage which moves with a master mounted thereon, a projection optical system, a lens-barrel platen supporting the master stage and the projection optical system, and a plurality of second mounts interposed between the lens-barrel platen and the floor or the member substantially equivalent to the floor to elastically support the lens-barrel platen from the lower side, wherein when viewed from an upper side, at least two of a barycenter position of a polygon defined by the plurality of first mounts, a barycenter position of a polygon defined by the plurality of second mounts, and an optical axis of the projection optical system substantially match.
In the exposure apparatus according to the 11th aspect of the present invention, preferably, when viewed from the upper side, all of the barycenter position of the polygon defined by the plurality of first mounts, the barycenter position of the polygon defined by the plurality of second mounts, and the optical axis of the projection optical system substantially match.
In the exposure apparatus according to the 11th aspect of the present invention, preferably, when viewed from the upper side, the master stage moves in a horizontal direction to cross the barycenter position or optical axis.
An exposure apparatus according to the 12th aspect of the present invention comprises a substrate stage which moves with a substrate mounted thereon, a base member supporting the substrate stage, a first reaction force reception structure for receiving a reaction force generated upon driving the substrate stage, a master stage which moves with a master mounted thereon, a projection optical system, a lens-barrel platen supporting the master stage and the projection optical system, and a second reaction force reception structure for receiving a reaction force generated upon driving the master stage.
In the exposure apparatus according to the 12th aspect of the present invention, preferably, the apparatus further comprises a first mount interposed between the base member and a floor or a member substantially equivalent to the floor to elastically support the base member from a lower side, and a second mount interposed between the lens-barrel platen and the floor or the member substantially equivalent to the floor to elastically support the lens-barrel platen from the lower side, and the base member and the lens-barrel platen are independently supported by the first and second mounts, respectively.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises an actuator for generating a force corresponding to the reaction force generated upon driving the substrate stage to reduce the influence of the reaction force.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises an actuator for generating a force corresponding to the reaction force generated upon driving the master stage to reduce the influence of the reaction force.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises a first actuator for generating a force corresponding to the reaction force generated upon driving the substrate stage to reduce the influence of the reaction force, and a second actuator for generating a force corresponding to the reaction force generated upon driving the master stage to reduce the influence of the reaction force.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises an elastic support interposed between the first reaction force reception structure and a floor or a member substantially equivalent to the floor to elastically support the first reaction force reception structure.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises an elastic support interposed between the second reaction force reception structure and a floor or a member substantially equivalent to the floor to elastically support the second reaction force reception structure.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises a first elastic support interposed between the first reaction force reception structure and a floor or a member substantially equivalent to the floor to elastically support the first reaction force reception structure, and a second elastic support interposed between the second reaction force reception structure and the floor or the member substantially equivalent to the floor to elastically support the second reaction force reception structure.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises a control section for controlling the actuator in accordance with the drive of the substrate stage.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises a control section for controlling the actuator in accordance with the drive of the master stage.
The exposure apparatus according to the 12th aspect of the present invention preferably further comprises a control section for controlling the first actuator in accordance with the drive of the substrate stage and controlling the second actuator in accordance with the drive of the master stage.
In the exposure apparatus according to the 12th aspect of the present invention, the control section preferably performs feedforward control of the actuator in correspondence with acceleration or deceleration of the substrate stage.
In the exposure apparatus according to the 12th aspect of the present invention, the control section preferably performs feedforward control of the actuator in correspondence with weight movement according to movement of the substrate stage.
In the exposure apparatus according to the 12th aspect of the present invention, preferably, the apparatus further comprises a measurement device for measuring an acceleration of the substrate stage, and the control section controls the actuator on the basis of a measurement result by the measurement device.
A device manufacturing method according to the 13th aspect of the present invention comprises the step of transferring a pattern onto a substrate using the above exposure apparatus.